Lawrence Brewers Guild

Over the last couple of weeks, my unheated garage dips below 32 deg regularly, probably down to 25 or so, but not enough to freeze a keg solid. My question: will the quality of beer (in serving kegs) be affected by freezing/thawing cycles? How will it affect carbonation?
I discovered that it was cold enough to freeze when yesterday I transfered a keg of cider (secondary) into a serving keg and observed about 6" of slush in the bottom of the secondary. I want to store my 5 serving kegs out there.

The biggest thing it will probably do is advance the aging of the beer. The other thing it'll do is cause more precipitation of solids, which in some cases would be a good thing such as clarity, and in others a perception of mouth feel could be lost. Since the beer is not getting to 75+ F-- probably not that bad. The freezing and thawing I would imagine could affect kegs that were not on a co2 bottle's constant pressure. As temp rises so goes the gas... IE the lace and head might not be aa thick and tight.

All in all though probably not that much of a whoop. If you could store on your basement floor, at a more constant temperature, it might be an overall better choice.

You are doing what the Germans do to create an Eisbock, if you separated the beer from the ice crystals.

The CO2 that is in the keg will still be there at a lower pressure because of the lower temperature.

[quote="klickcue"]You are doing what the Germans do to create an Eisbock, if you separated the beer from the ice crystals.quote]
Yeah, except I'm letting it "reconstitute" when the temp rises.

Dale Wheeler wrote:I transfered a keg of cider (secondary) into a serving keg and observed about 6" of slush in the bottom of the secondary

That's how they made "Apple Jack" in the old days.
j

PV = NRT

A formula which deals with the relationship between a gases volume, the pressure, the molecular concentration for the substance media and the temperature in kelvin.

Beer is an interesting critter. With your beer at near freezing temps, it will actually take on more CO2 per unit of volume than it would at higher temp. More CO2, more formation of carbonic acid. As carbonic acid is a very, very, very weak acid, it should not effect the end result.

The big issue with frezzing water is 2 fold

1. When you freeze water it expands by the formation of crystals. The size of these crystals will be directly proportional to how fast the water is frozen. Flash freeze it, small crystals. Slow freeze, huge honking crysatals. Now if you are a cell in a water soluiton and you are frozen slowly, the large crystals will punchure the cell walls and make it a bad day. If flash frozen, smaller crystals form and less damage to cells. An example is freezing yeast. I place my yeast villes in the fridge for a couple of days to get them as cold as possible before sticking them in the freezer. This shortens the freeze time and thus produced smaller ice crystals and happer yeast.

2. Lowering the temperature slows everything down. If you have yeast cell doing their thing, they will slow to a crawl as they approach freezing. Freeze the beer to slow, and you could kill all the yeast (what i do to cold-crash my beer before kegging) this is of course dependent on the type of yeast and there surroundings. So if you are looking to naturally carbonate your beer at 32...may take a while. But if you want to help clarify your beer by cold crashing it for a week, the inactive yeast will fall to the bottom.

Freezing can also be a way to concentrate a solution. Ethanol, Esters and some other chemicals have lower freezing points, so if you freeze the water the other chemicals will stay in solution and not in the ice. By removing the ice, you have just concentrated the final solution.

Your beer will be fine!

Jason